Try nesting them. The multipart/alternative content type is meant more for saying "I can show you this type of content, or this type, you decide." You're doing it right with the multipart/related to combine images with an HTML content type. 
multipart/alternative
   multipart/related
      text/html
      image/gif
      whatever/else
   text/plain (a plain-text version)

[download]
If that doesn't work, I might want to see the actual output of your script, if you can reduce it to something small-ish.

In reply to Re: Re: Re: Sending HTML Mail by Fastolfe
in thread Sending HTML Mail by neilwatson

Title:
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and:  <code> code here </code>
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